The debut shattered the record previously held by Matt Damon's The Bourne Ultimatum, which bowed to $69 million in August 2007.

Analysts expected a No. 1 opening of at least $70 million, but the debut still surprised because Guardians is a new franchise.

"None of the characters involved in this movie are considered seminal to the Marvel universe in the way that Captain America, Thor, The Hulk and Iron Man are," says David Mumpower, analyst for Box Office Prophets.

"Simply stated, the Marvel brand has become for Disney what the Pixar brand had been through 2010," Mumpower says. "Consumer trust in the Marvel product is total. Even virtually unknown characters can still anchor a blockbuster debut."

This is Marvel's fourth film to open above $90 million this year, thanks to "the strength of the Marvel brand," says Rentrak's Paul Dergarabedian.

Mumpower notes that Guardians flourished without the "Avengers bump," the box-office surge that has boosted ticket sales for every character that appeared in the 2012 all-star superhero team.

"The Avengers bump is no longer exclusive to Avengers characters," Mumpower says. "A superhero space team of similar composition has been accepted by consumers as a worthy Avengers substitute while they wait for Age of Ultron," the Avengers sequel coming next year.

Lucy, Scarlett Johansson's thriller, took second place with $18.3 million.

Get On Up, the James Brown biopic, took third place with $14 million, meeting most expectations. It earned solid scores from fans and critics, scoring an A from moviegoers and a recommendation from 77% of reviewers.

The swords-and-sandals epic Hercules claimed fourth with $10.7 million, followed by Dawn of the Planet of the Apes with $8.7 million.